Gripper mechanism for printing presses



Oct. 6, 1936. w. GEGENHEIMER 2,056,922

GRIPPE'R MECHANISM FOR PRINTING PRESSES Filed Oct. 20, 1954 2 Sheets-Sheet. 1

ATTORNEY Oct. 6, 1936. w. GEGENHEIMER GRIPPER MECHANISM FOR PRINTING PRESSES Filed Oct. 20, 1934 ,2 Sheets-Sheet 2 ATTORN EY Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE GRIPPER MECHANISM FOR PRINTING PRESSES Application October 20, 1934, Serial No. 749,244

2 Claims.

This invention relates to gripper mechanism for receiving and holding successive sheets fed to the impression or feed cylinder of a press, such, for example, as an offset press. In such apparatus, a plurality of fingers are carried by the cylinder and the fingers are opened and then closed upon a sheet placed in register therewith by the ordinary paper feed of the machine, the fingers being released after the printing impression is completed on the sheet by rotation of the feed cylinder.

According to the present invention, the gripper fingers are mounted in such manner as not only to have a pivotal or rocking action with respect to the cylinder, but a bodily movement coaxially with the cylinder in an arcuate path toward and from the point at which the sheet is received by the cylinder in position to be grasped by the fingers. Such movement is a positive movement independently of the rotation of the cylinder.

A characteristic of my construction is that the gripper fingers are held against bodily movement, preparatory to gripping the paper, during a movement of the cylinder relative to the gripper mechanism and when the cylinder moves a predetermined distance the fingers will meet the sheet and hold the same against a gripper bar whereupon the gripper mechanism will move in unison with the cylinder.

The invention will be described with reference to the accompanying drawings, in which- Fig. 1 is an end elevation of a printing cylinder and a supporting frame therefor together with the gripper mechanism of the present invention, certain parts being broken away and others being shown in dotted lines, the gripper being shown open.

Fig. 2 is a diagrammatic view similar to Fig. 1, showing the gripper elements in closed position.

Fig. 3 is a fragmentary front elevation of a printing cylinder, its supporting frame and gripper mechanism of the present invention.

Fig. 4 is a perspective view of the printing cylinder and certain elements of the gripper mechanism.

In the drawings I have shown a printing cylinder at I, the latter having an open gap from the line A to the line B. One end only of the cylinder is shown, to wit, that end carrying the operating mechanism for the gripper fingers. The cylinder is provided with the usual end plates Ix, Izcx, the latter having a hub 2 rotatably mounted in fixed frame member 3, hub 2 directly engaging a bushing 4. Extending through the cylinder coaxially therewith and with hub 2, is a shaft 5 which is adapted to turn independently of the cylinder. This shaft is employed to transfer operative movements to the gripper shaft and fingers later to be described. 5

Secured to hub 2 of the cylinder I by means of screws 6, is a plate I, which turns with the cylinder. Adjacent plate I and keyed to shaft 5 is a gear segment 8 which meshes with an actuating gear segment 9, the latter being carried by a pivot 10 stud I0 carried by plate I.

Below gear segment 9 is a stop arm I I, the latter being pivoted at I2 upon frame member 3. Arm II carries a roller I3 in register with a cam I4 mounted for rotation in the direction of the 15 arrow, Fig. 1. Stop arm II also carries a roller I5 adapted to be engaged by a finger 93: carried by gear segment 9.

Clamped on shaft 5 by means of strap I6 and bolts II is a bracket arm I8 disposed within the open gap A-B of the cylinder. It will be understood that a second bracket arm I8 will be disposed at the opposite end of the cylinder, and intermediate arms, in order that they may adequately support the gripper shaft, gripper bar 25 and associated gripper mechanism. Arm I8 is provided with a boss Him to receive gripper shaft I9, the latter carrying the usual grippers 20, and secured to arm I8 by screws 24 is gripper bar 2I. Gripper shaft I9 projects beyond the end of boss 30 I8x and has secured thereto a lever 22 provided with a contact roller 23 engaging the undersurface of a cam 25 secured to end plate In: by screws 26.

The formation of cam 25 is best shown in the dotted line views Figs. 1 and 2. 35

Pivotally mounted on a shaft 21 disposed above the cylinder and in register with gripper bar 2| is a shouldered latching arm 28, the function of which will be hereinafter set forth.

In the operation of the device, the cylinder I will travel at a constant rate of speed in a counter-clockwise direction, as indicated by the arrow a. In the normal position of the gripper mechanism, gripper bar ZI will lie against the edge of cylinder gap B and the cylinder therefore will bodily move the arm and associated gripper mechanism in the direction of the arrow. This follows because gear segment 9 is engaged by a heavy spring 29 which turns the segment and therefore gear segment 8 with shaft 5 and bracket arm I8 until gripper bar 2I engages the edge of the cylinder gap at B. As the cylinder rotates in the direction of the arrow a, finger 9.1: will meet roller stud 23 and gear segment 9 will be given a reverse rotation which will result in the moving of arm l8 and the associated gripper mechanism to the position shown in Fig. 1. In such movement of the gripper mechanism, roller 23 and lever 22 will ride up upon a high point of cam 25 and thus to the position of Figs. 1 and 4. By such movement, lever 22 will turn gripper shaft 19 to raise the gripper fingers 20 above bar 2|, the parts assuming the position of Figs. 1 and 4. At this point, the gripper bar 2| will have passed the shoulder 28a: of latching arm 28 and the arm will move downward to the position shown in Figs;

1 and 4, the spring 29 acting upon segment gear 9 to hold the arm in such position until the cyle inder moves ahead to bring the edge B of the cylinder gap into contact with the gripper bar. In the meanwhile, a sheet of paper is passed by the feeding means (not shown) along plate 30, entering the space between the gripper fingers 20 and gripper bar 2| and in the movement of the cylinder, as just described, the high point of cam 26 will be carried away from 23 and shaft l9 will be partially rotated by its usual spring (not shown) to carry the gripper fingers down upon the paper holding the same against the gripper bar 2!. Thus, when the edge B of the cylinder gap meets the gripper bar, the sheet of paper firmly held by the gripper mechanism will be carried with the cylinder. This is permitted by the actuating mechanism for gear segment 9 as will be seen by reference to Fig. 1. In that figure, the gripper bar has just been engaged by latching arm 28 and the low point of cam I4 is approaching roller l3 immediately thereafter releasing the stop arm so that it falls to the position shown in Fig. 2 enabling the bodily movement of gear segment 9 and its associated parts with the cylinder. When the printing impression upon the paper has been completed, cam M will have raised stop arm ll, placing roller stud I5 in register with finger 91:. As the cylinder rotates, finger 9:1: engages roller stud l5 and gear segment 9 is swung to the position of Fig. 1, releasing the paper. Thus, after the printing impression the paper is released at an adequate interval before a new sheet is moved to position between the gripper bar and gripper fingers.

For ease and smoothness of operation, arms l8 may be counterbalanced, as, for example, by continuing the metal of strap I6 downwardly to form "of the gap, means for rotating the cylinder, a

shaftmovable independently of the cylinder, carrying means on said shaft and disposed in said gap, gripper fingers pivotally mounted on said carrying means, a cam device carried by the cylinder and adapted to rock said fingers, a gear on said shaft, and a second gear in mesh therewith and having a contact finger, a spring acting upon the second gear and normally actuating said gears to hold the carrying means against a cylinder wall at one edge of the gap, contact means in the path of said finger for rotating said second gear against the tension of the spring, and means for releasing said contact means from engagement by said finger.

2. In gripper mechanism for cylinder printing presses, a cylinder having a peripheral gap therein bounded by cylinder walls at the opposite edges of the gap, means forrotating the cylinder, a shaft movable independently of the cylinder, carrying means on said shaft and disposedjin said gap, gripper fingers pivotally mountedon said carrying means, a cam device carried by the cyl-. inder and adapted to rock said fingers, a gear on said shaft, and a second gear in mesh therewith, a spring acting upon said gears to normally hold the carrying means in such position that the gripper fingers are held adjacent one cylinder wall at an edge of the gap, means for rotating said gears against the tension of the spring during a partial rotation of the cylinder, a contact member on said second cam and means movable into and out of register with said contact member whereby the second gear during partial rotation of the cylinder is given a rotational movement against the tension of said spring and thereafter is released.

WILLIAM GEGENHEIMER. 

